In the forming of certain relatively hard materials using procedures and apparatus that are current in the industry, the deformation of the material caused by the forming operation must be above some minimum value or fracturing of the material at or near the deformation will occur. For example, in the case of bending, either the radius or the degree of bend must be above some minimum value. It is commonly believed that the material work hardens as the forming takes place and then fractures as bending continues and the elastic limit of the material is exceeded at the work hardened area. Heat treatment procedures have been developed for some materials, such as hard aluminum alloy used in the aircraft industry that, coupled with the forming operation, allow limited forming without fracturing. However, these procedures are cumbersome, expensive to implement, and limited to a few relatively hard materials. Certain materials, however, cannot be meaningfully formed at conventional stamping and forming speeds and there are no heat treatment procedures available that will enable these materials to be easily formed. An example of such a material is Paliney 7, a high strength palladium gold alloy, in its full hard condition of about 195,000 pounds per square inch ultimate tensile strength, manufactured by J. M. Ney Company of Hartford, Conn. The forming of this material at normal stamping and forming speeds is limited to a certain minimum radius, however, as will be explained below, forming of this material to a much smaller radius is possible utilizing the method taught by the present disclosure. It is known that certain explosives can be utilized to successfully form some relatively hard materials. For example, Lead Azide, which has a shock wave velocity of over 20,000 feet per second has been used to bend and even weld materials that would generally fracture when bending and forming is attempted using conventional processes and equipment. This procedure is generally used with relatively large components such as ends for large tanks, autoclaves, boilers and similar structures. However, the use of explosives to form small parts such as electrical contacts for electrical connectors is unknown and deemed impractical.
What is needed is a method of easily forming these relatively hard materials in the manufacture of relatively small parts such as electrical contacts without resorting to complex heat treatment procedures or methods that employ dangerous explosives. Manually bending a piece of wire back and forth to break it causes a substantial temperature rise in the area of the bend. This local temperature rise is proportional to the speed of bending. Forming these materials at a high speed is perceived to generate sufficiently high temperatures in the forming area to make it behave as if annealed, and further, if the forming is accomplished in a period of time which is shorter than the stress relaxation constant of that material, the forming limit of the material is substantially improved.